<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <ul id="ul"></ul>
  <button id="btn">确认</button>

  <script>
    let arr = ['html', 'css', 'js', 'vue']

    arr.forEach((item, i, arr) => {
      let li = document.createElement('li');
      li.textContent = item;
      document.getElementById('ul').appendChild(li);
    });
  </script>

  <script>
    document.getElementById('btn').addEventListener('click', function () {
      this.innerText = '提交'
    });
  </script>
</body>

</html>